What is Synesthesia?
Synesthesia refers to a perceptual phenomenon that works on the stimulation of one sensory or cognitive pathway, which further leads to involuntary experiences in a second cognitive or sensory pathway. People known to experience a long history of such instances are known as synesthetes.
The awareness of synesthetic perceptions varies from one person to another. In the usual form of Synesthesia, also known as Color–graphemic Synesthesia or Grapheme-color Synesthesia, letters and numbers are perceived as inherently colored. Additionally, in number form Synesthesia or spatial sequence, numbers, months of the year, or days of the week denote precise locations in space.
Synesthetic associations can occur in any number of senses or a combination of cognitive routes. There is close to no information on how Synesthesia develops in a person. Many studies have concluded that Synesthesia develops in a person during childhood. This is because children are intensively engaged with abstract concepts in their youth.
This hypothesis is referred to as the semantic vacuum hypothesis. This hypothesis explains the most common forms of Synesthesia. These forms are spatial sequence, grapheme-color, and number form. Generally, these are the first abstract concepts that any educational system requires children to learn. Many different phenomena have been included in the term Synesthesia. A more accurate but less common term for the same phenomenon is ideasthesia.
The earliest case of Synesthesia ever recorded is attributed to John Locke, an Oxford University academic and philosopher. Locke made a report in 1690, which elaborated on a blind man who experienced the color scarlet whenever he heard the trumpet sound. However, there has been much disagreement about whether Locke described an actual instance of Synesthesia or used a metaphor in his writing. The first medical account of Synesthesia came in 1812 from German physician Georg Tobias Ludwig Sachs.
History
The interest in colored hearing can be traced back to Greek antiquity. This notion was also mentioned in Indian classical music in examples of the musical terms raga and rasa, which are also synonyms for color and the quality of taste, respectively. The German physician Georg Tobias Ludwig Sachs noted the first medical description of “colored hearing” in an 1812 thesis. This was followed by Carl Jung referring to “color hearing” in 1912 in his Symbols of Transformation.
Research and further study into Synesthesia proceeded in various countries. Still, due to the hassles in measuring any subjective experience and the rise of behaviorism during that time (which made the study of subjective experience taboo), the study of Synesthesia and its components faded into the scientific background between the 1930 and 1980. After the 1980s cognitive revolution, the idea of inquiring into an individual’s internal subjective states became respectable again. This was when scientists returned to the concept of Synesthesia for further research. This research was led in the United States by Richard Cytowic and Larry Marks and later in England by Jeffrey Gray and Simon Baron-Cohen, who were all famous researchers of their times. They explored the consistency, reality, and frequency of synesthetic experiences.
Neuroscientists and Psychologists study Synesthesia for the insights it gives into cognitive and perceptual processes. These processes occur in non-synesthetes and synesthetes alike. Synesthesia is now the idea that appears in a lot of Ph.D. theses, scientific books and papers, novels, and even documentary films.
These rapidly grew into international organizations since the rise of the Internet in the 1990s. Some influential organizations are the American Synesthesia Association, the UK Synaesthesia Association, the Belgian Synesthesia Association, the Canadian Synesthesia Association, the German Synesthesia Association, and the Netherlands Synesthesia Web Community.
Types
There are two forms of Synesthesia understood as of now:
— Projective Synesthesia is about seeing forms, colors, or shapes when stimulated. This is also known as the widely understood version of Synesthesia.
— Associative Synesthesia is about feeling an involuntary and robust connection between a stimulus and the sense this stimulus triggers.
For example, in chromesthesia (sound to color), an associator might hear a trumpet and think strongly that it sounds “orange.” On the other hand, a projector may listen to a trumpet and see an orange triangle in space.
Synesthesia can occur between any two senses. Types of Synesthesia are denoted by the notation x → y, where x is the trigger or “inducer” of the experience, and y is the “concurrent” or other experience—for instance, perceiving specific letters and numbers (collectively called graphemes) as colored would be denoted as grapheme-color Synesthesia.
Similarly, when synesthetes can see colors and movement as a consequence of hearing musical tones, it would be denoted as tone → color, movement, and Synesthesia. While nearly every logically possible combination of experiences can occur, several types are more common than others.
Signs and Symptoms
Some synesthetes report being unaware of their experiences until they realize others did not have them. Others felt that they had been keeping a secret. Most synesthetes have said these experiences to be pleasant or neutral. Although, sometimes, they may even lead to sensory overload in the person who experiences them.
Most synesthetes become aware of this distinctive mode of perception in their early childhood. They use these abilities for memorizing names, mental arithmetic, telephone numbers, and more complex creative activities such as producing music, visual art, and theater.
Despite the commonalities, individual experiences vary in several ways. While some synesthetes report that vowels are more intensely colored, others feel that consonants are more strongly colored. Self-reports, autobiographical notes, and interviews by synesthetes demonstrate significant variation.
Synesthetes are most likely to participate in creative activities. This interest has been suggested because individual development of cognitive and perceptual skills, in addition to one’s pre-existing cultural environment, is said to produce a variety in awareness and the practical use of the synesthetic phenomena. Synesthesia is also known to give a memory advantage.
According to a study by Julia Simner of the University of Edinburgh, spatial sequence synesthetes have a built-in and automatic mnemonic reference that helps them in situations requiring them to jog their memory. On the other hand, a non-synesthete will need to create a mnemonic device to remember a sequence. An example of such a device is like dates in a diary. A synesthete can reference their spatial visualizations, but a non-synesthete cannot. It is a perceptual phenomenon where activation of one sensory or cognitive channel leads to involuntary experiences in another sensory or cognitive pathway. Synesthetes are people who have had such experiences for a lifetime. Synesthetic awareness varies from person to person. Grapheme–color synesthesia, or color–graphemic synesthesia, causes letters or numbers to appear coloured. Numbers, months of the year, or days of the week might evoke particular locations in space (for example, 1980 may be “far distant” than 1990), or appear as a three-dimensional map (clockwise or counterclockwise). Synesthetic associations can occur across many senses or cognitive pathways. Synesthesia is a rare condition. Synesthesia may emerge in childhood when children are first exposed to abstract concepts. This concept explains why the most prevalent synesthesias are grapheme–color, spatial sequence, and number form. These are frequently the first abstract notions taught in schools. Synesthesia is a difficult concept to define. Synesthesia (from the Greek words v and, meaning “union of the senses”) has been used to a wide range of experiences, and the concept is often misleading. Ideasthesia is a more accurate but rare term. In 1690, the Oxford professor and philosopher John Locke reported about a blind man who believed he sensed the colour crimson after hearing a trumpet. However, whether Locke portrayed a real incident of synesthesia or used a metaphor is debated. The first medical report was by Georg Tobias Ludwig Sachs in 1812. The word comes from the Greek syn and aisthsis, which means “together”.